| 摘要 |
PURPOSE:To prevent generation of microdefects such as microblowholes and slag inclusion and to improve the cracking resistance and mechanical properties of a weld metal and welding workability by specifying the contents of Ni and oxygen in a core wire and coating the core wire with a coating material which is specified in the compsn. CONSTITUTION:The core wire contains Ni at >=98% and is controlled in the content of oxygen to <=0.008%. The coating material contains, by the total weight of the coating material, 10-25% metal carbonate and 10-25% metal fluoride in such a manner that the ratio of the metal carbonate/metal fluoride attains 0.70-1.40. The coating material further contains 1 or >=2 kinds among 0.8-7% Ti oxide, 0.8-7% Zr oxide, 0.5-6% Fe oxide, 0.5-6% Mn oxide, 0.5-6.5% Cr oxide, and 0.5-6.5% Ni oxide in such a manner that the total thereof is 1.5-8%. The core wire consists essentially of 18-30% Cr, 6-15% Mo and 2-10% Mn in terms of the weighty ratio thereof, contains 1.5-5.0% in total 1 or >=2 kinds among 1.0-3.0% Al, 0.5-2.5% Ti and 0.5-2.5% Si and is specified to <=0.25% total moisture content. |
